gem-Selective Cross-Dimerization and Trimerization of Alkynes with Silylacetylenes Promoted by a Rhodium-Pyridine-N-Heterocyclic Carbene Catalyst
نویسندگان
چکیده
gem-Selective cross-dimerization and trimerization of silylacetylenes with alkynes via C-H activation using a rhodium(I)-pyridine-Nheterocyclic carbene catalyst have been developed. This protocol is applicable to variety of aliphatic or aromatic terminal alkynes, internal alkynes and gem-1,3-disubsituted enynes to afford the corresponding enynes and dienynes with high regioand stereoselectivities and good isolated yields (up to 91%).
منابع مشابه
Pyridine-enhanced head-to-tail dimerization of terminal alkynes by a rhodium-N-heterocyclic-carbene catalyst.
A general regioselective rhodium-catalyzed head-to-tail dimerization of terminal alkynes is presented. The presence of a pyridine ligand (py) in a Rh-N-heterocyclic-carbene (NHC) catalytic system not only dramatically switches the chemoselectivity from alkyne cyclotrimerization to dimerization but also enhances the catalytic activity. Several intermediates have been detected in the catalytic pr...
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